San Francisco Police Chief Greg Suhr said two men are in custody for the stabbing death of a Dodgers fan. / Jeff Chiu AP

by Jorge L. Ortiz, USA TODAY Sports

by Jorge L. Ortiz, USA TODAY Sports

SAN FRANCISCO - The memory of Bryan Stow's brutal beating has been rekindled, with an even more tragic twist.

A 24-year-old son of a Los Angeles Dodgers security guard clad in the team's gear was stabbed to death near AT&T Park late Wednesday night following a fight sparked by an argument over the Dodgers and their longtime rivals, the San Francisco Giants.

San Francisco Police Department Chief Greg Suhr identified the man as 24-year-old Jonathan Denver, who the Dodgers later confirmed is the son of one of their security guards. Sgt. Danielle Newman said Michael Montgomery, 21, of Lodi, Calif., was arrested on murder charges. Police were seeking information on two other suspects.

The fatal stabbing took place 2½ years after Stow, a paramedic from Santa Cruz and a Giants fan, was beaten unconscious during an attack in the Dodger Stadium parking lot on Opening Day 2011. He sustained permanent brain damage and remains under constant home supervision.

"We've all heard about the Bryan Stow (attack) down in L.A. and you'd think people would learn from stuff like that,'' Dodgers second baseman Mark Ellis said. "If they're arguing about the teams, it's great to be a passionate fan, it's awesome. But to take it that far, it's crazy. You get alcohol involved and nothing good ever happens."

Suhr said Denver attended Wednesday's Dodgers-Giants game with his father, girlfriend, two brothers and a male friend, and they left in the eighth inning around 10 p.m. to go to a nearby bar.

Some 90 minutes later, they had a street confrontation with four Giants fans who did not attend the game but came into town for an event at a bar about half a mile from the ballpark. Suhr said the groups had an exchange about the teams' rivalry and it turned into a fight, but was broken up without serious injuries.

Shortly afterward, he added, the parties engaged in a second altercation that resulted in Denver's fatal stabbing on Stillman Street, located under a freeway overpass around the corner from several bars and restaurants. Police were looking for the murder weapon and seeking help from anybody who may have taken video of the events.

"There is no place at these games for violence,'' Suhr said in a news conference Thursday. "Nobody's life should be at stake, whether they're at the game, or six blocks away and an hour and a half after the game.

"That anybody got into any sort of beef over the Giants and the Dodgers and somebody lost their life, it is just senseless.''

Police presence at and around the ballpark, already enhanced under what the SFPD calls the "Rivalry Package,'' was boosted even more, with some officers dressed in Dodgers attire.

"I thought about not wearing my gear tonight, but then I thought that it'll probably be the safest night of the year, what with all the extra security," said Clay Brust, a 44-year-old lawyer from Reno who wore a Dodgers cap and brought his 11-year-old son to the game. "I've been to Raiders games, and those are scary. I've never seen it get bad in the Giants-Dodgers rivalry. There are verbal jabs, but they always end with joking."

Giants third base coach Tim Flannery, also a musician who has played benefits concerts and recorded an album to raise money for Stow's medical costs, has noticed a change in the ballpark culture.

"It's such a tragic, tragic piece of humanity that we even have to discuss something like this happening," Flannery said. "I don't consider this to be something that happened between fans-it's a hate crime. These aren't rivalries, these aren't fans-they're thugs. It comes from a place of anger and rage.

"There's no way I believe that fans come to a baseball game to fight. This is something thugs do. People of hate just use the game as a place to have that happen. To ruin lives over a nine-inning baseball game is just crazy.

"From my third-base coaching box, I've watched the rage in the stands escalate over the last five or six years. It's greater now than I've ever seen it. That's society. I really don't know what's going on."

The Giants issued a statement denouncing the violence and announced they would hold a moment of silence before Thursday night's game.

"We're here to provide entertainment and a release from people's everyday lives-not to incite violence," said Giants reliever Javier Lopez. "When you hear these stories, your heart just goes out to the victim."